From Beaumont Physicians and Allied Health Professionals
Summer Issue 2012
A new window into the heart – Cardiac MRI DIAGNOSTIC TESTING
Michael Gallagher, M.D. Director, Advanced Cardiac Imaging Beaumont Hospital, Royal Oak
Over the past decade, advances in science, physics and medical technology have allowed doctors to examine the heart with a new camera. Cardiac magnetic resonance imaging (MRI) can actually take pictures of a beating heart. The pictures obtained through this new “lens” offer an alternative to the more common imaging tests such as heart ultrasound (echocardiography), nuclear imaging, and computed tomography scans. In fact, cardiac MRI has rapidly become a useful imaging test to diagnose many heart conditions. What is a Cardiac MRI? Cardiac MRI is a safe, non-invasive medical test that creates detailed pictures of the heart using a specialized camera. MRI uses radio waves (radio frequency pulses), a powerful magnetic field, and a computer to make pictures. Doctors use cardiac MRI to assess the heart anatomy and function, as well as major blood vessels. Detailed MRI images help determine the presence of certain diseases that may not be identified with other imaging methods. Why did my doctor choose an MRI of the heart? MRI images of the heart are very clear, making the test invaluable for several conditions. Some common reasons to have the test include: • To further investigate any abnormalities seen on other heart imaging tests • To monitor heart muscle function, thickness and size (weak and dilated hearts called “cardiomyopathies” are accurately imaged with this test) • To assess the amount of heart damage caused by a heart attack; and to determine if heart function has potential to improve after stent placement, bypass surgery or medical therapy. MRI is able to detect areas of heart tissue that have poor blood supply (due to coronary artery disease) or that has been damaged (from a heart attack)
• To evaluate structures in and around the heart, such as the pericardium (sack around the heart) and the aorta. MRI can also locate and characterize any rare tumors around the heart • To better understand abnormalities of the heart the patient may have been born with (congenital heart defects) The test: What should I expect; is it safe? The test takes approximately one hour. It is an extremely safe test without any radiation exposure. The exam causes no pain. It is normal for the area of the body being imaged to feel slightly warm from the magnetic pulses. Although the strong magnetic field is not harmful, implanted medical devices that contain metal may malfunction or cause problems during an MRI (so tell your doctor if you have a pacemaker, defibrillator, or other implanted metallic devices).
INSIDE THIS ISSUE
A new window into the heart – Cardiac MRI 1 Aerobic exercise intensity: What’s my range? 2 Unhealthy eating: Cows, pigs and chronic disease 3 The mystery of the stethoscope explained 4 Can pets influence our response to stress? 5 Atrial fibrillation: Treatment options 6 Common antibiotic increases risk of cardiovascular death 7 Flu facts for the cardiac patient 8 The problem with abruptly stopping beta-blocker therapy 8 Exercise: The antidote to aging? 9 Aneurysms: A bubble in the vascular system? 10 Common Q & A 11
E X E R C I S E A P P L I C AT I O N S
Aerobic exercise intensity: What’s my range? Jake Terrell, B.S. Preventative Cardiology and Rehabilitation Beaumont Hospital, Royal Oak
Cardiovascular exercise is an essential part of living a healthy and active life. Engaging in regular, planned bouts of aerobic exercise can help prevent, as well as manage, chronic disease. Whether you are a cardiac patient enrolled in a rehab program after experiencing a heart attack or simply someone who wishes to have more endurance in their daily life, exercise is an essential tool for improving heart and lung fitness. The American College of Sports Medicine recommends aerobic exercise three to five days per week, 20 to 60 minutes per session, to achieve and maintain health and fitness benefits. But how intense should your treadmill walk or stationary bike ride be during that time? Much like the medications that you may take, aerobic exercise intensity can also be prescribed. A common method for prescribing exercise is to determine your maximal heart rate and select a safe and effective submaximal heart rate range to exercise within. A normal resting heart rate generally approximates between 60 and 90 beats per minute, increasing as you begin to exercise. As exercise becomes more intense (e.g. the treadmill speed and/ or grade increases), the heart rate increases in order to provide oxygenated blood to the working muscles. In the cardiac rehab setting, many patients undergo a peak or symptom-limited exercise stress test prior to starting the program. This test records, among other important responses, your peak or maximal heart rate, which can be used to establish a safe and effective range to exercise within. This reduces the likelihood that exercise will be prescribed below the threshold needed for favorable adaptation and improvement, above too vigorous an intensity, or beyond the heart rate that may evoke signs or symptoms of strain or significant heart rhythm irregularities. Using the maximal heart rate that is obtained during a medically supervised exercise test is an accurate way of 2
prescribing exercise intensity; however, access to this information may not be readily Don’t make available for many people exercising at exercise a chore, local fitness centers. but rather In the absence of an exercise stress test, a reward. the equation 220 – age is sometimes used to estimate maximal heart rate. Taking 65 to 80 percent of this value would then be used to set an exercise range. However, this method has numerous limitations. Your true maximal heart rate can vary considerably depending on the medications you are taking and your overall health. Therefore, this may not necessarily be an Physical Exertion Scale accurate or particularly 6 No exertion at all effective way to 7 Extremely light 8 determine your aerobic 9 Very light Recommended exercise intensity. 10 Exercise
12 Intensity The Borg Rating of 13 Somewhat hard 14 Perceived Exertion Scale 15 Hard (heavy) offers another way to 16 17 Very hard determine exercise 18 19 Extremely hard intensity without having 20 Maximal exertion to depend on heart rate monitoring. The Borg scale starts at six and ends at 20, with some of the intervening numbers having descriptive effort ratings. Using this scale, you simply choose a number or word phrase for how intense your exercise session feels, taking into account leg fatigue, breathing and overall physical effort. For health and fitness benefits, it is best to exercise between a nine and 13 on the Borg scale, which corresponds to very light to somewhat hard effort. Within this perceived exertion range, your heart rate and breathing will be somewhat higher than at rest. However, you should still be able to carry on a conversation during exercise at this intensity.
The best approach to any exercise program is to start slowly and progress gradually. One way to do so is start with shorter bouts of 10 minutes at a time, two to three times per day. Always warm up five to 10 minutes before exercise with a slow pace and cool down afterwards by comfortable walking. Finally, enjoy being physically active. Don’t make exercise a chore, but rather a reward. Once you start looking forward to exercising, you’ll become healthier for it.
FROM THE EDITOR
Barry A. Franklin, Ph.D. Director, Preventive Cardiology and Rehabilitation, Beaumont Hospital, Royal Oak
Unhealthy eating: Cows, pigs and chronic disease A number of recent research studies show that certain dietary practices are associated with lower rates of chronic disease. In other words, what we include in our diet is as important as what we exclude. For example, “good” carbs (e.g., fruits, vegetables, whole grains) and fats (e.g., fatty acids found in fish oil, flaxseed oil) seem to be cardioprotective, whereas “bad” carbs (e.g., white bread) and fats (e.g., trans fats) are associated with a heightened risk of developing varied illnesses. Why is this so important? Because more than 75 percent of the $2.6 trillion in annual health care costs are spent in treating chronic diseases such as coronary heart disease. Healthier dietary practices are likely to lessen the consequences of these unhealthy conditions, thereby reducing health care costs. This premise was substantiated by a widely cited European study (Archives of Internal Medicine, Aug. 2009), which showed that patients who adhered to healthy dietary practices had a 75 percent lower overall risk of developing a chronic disease. Is processed and unprocessed red meat bad for you? In a word, yes. Earlier this year, the first large-scale prospective
longitudinal study in men and women showed that regular consumption of red meat is associated with an increased risk of premature death from all causes including cardiovascular disease and cancer (Archives of Internal Medicine, April 2012). In a related study by the same investigators, red meat consumption was associated with an increased risk of developing type 2 diabetes (American Journal of Clinical Nutrition, Oct. 2011). Thus, substituting healthier foods for red meat provides a double benefit to our health. Recently, a group of nutrition experts provided a series of recommendations for health practitioners, patients and policy makers to better understand contemporary issues related to the effects of diet on cardiovascular disease (Circulation, June 2011). Their dietary priorities for cardiovascular and metabolic health are summarized in the accompanying table (see page 11). In closing, I’d like to share a few relevant quotes that I’ve used in my teaching and presentations over the years with specific reference to healthy and unhealthy dietary choices. Enjoy!
“The whiter the bread, the sooner you’re dead.” – Zonya Foco, R.D.
“If you can’t be a vegetarian yourself, the next best thing is to eat a vegetarian from the sea.
“How do you make a hot dog? First you slaughter the animals and cut out all the good parts, the steaks and chops. But you’ve got a lot of animal left and what are you going to do with it? The hot dog industry took off when a clever guy invented a machine that works like a kitchen disposal – you dump everything in, eyeballs and all, and grind it up. Voila, the hot dog.” – William Castelli, M.D.
“Our excessive intake of meat is killing us. We fatten our cows and pigs, kill them, eat them, and then they kill us!” – William C. Roberts, M.D.
These are the mollusks – mussels, clams and oysters – the animals that are rock-bottom lowest in saturated fat. Even the crustaceans – shrimp and lobster, for example – are better to eat than the white breast of chicken without the skin because they are so low in saturated fat. The cholesterol in crustaceans has been recently reanalyzed and found to be much lower than we used to think.” – William Castelli, M.D.
CLINIC AL C ARDIOLOGY
The mystery of the stethoscope explained may reveal medical conditions such as high blood pressure or pulmonary hypertension, as well as pathology of the valves themselves.
Ivan Hanson, M.D. Cardiology Fellow Department of Cardiovascular Medicine Beaumont Hospital, Royal Oak
Have you ever wondered what a cardiologist hears when he or she listens to your heart? With the advent and refinement of non-invasive imaging tests, cardiac auscultation is becoming a lost art. However, the stethoscope remains one of the most useful clinical tools in the initial evaluation of many cardiovascular problems. The following is a brief synopsis of the link between heart sounds and cardiac function. A normal heart beats regularly at a rate of 60 to 90 times per minute. If the rhythm is irregular, it could mean that extra heartbeats are periodically resetting the normal rhythm. It could also mean that an abnormal rhythm, such as atrial fibrillation, has completely overridden the normal rhythm. The heart contains four valves that facilitate forward flow of blood from the low-pressure venous circulation to the high-pressure arterial circulation; aortic, pulmonic, mitral and tricuspid. Each normal heartbeat comprises two heart sounds, which are caused by valve closure. The first heart sound represents closure of the mitral and tricuspid valves, while the second heart sound represents closure of the aortic and pulmonic valves. Variations in the loudness of the first and second heart sounds
A murmur is a “whooshing” sound, which may signify that a valve is narrowed or leaky. The character, location and timing of the murmur help to identify the valve that is affected. The loudness of the murmur generally does not relate to severity. However, other physical examination findings are often useful in determining severity of the valve abnormality, which is usually confirmed by cardiac ultrasound (echocardiography). Severe valvular narrowing or leakiness may require surgical correction. Other abnormal sounds may be present in the setting of volume, pressure overload or inflammation around the heart. These sounds may not be consistently present each time a patient is examined, and may disappear with medical therapy of the respective underlying condition. The stethoscope is a gateway to cardiac function. Entirely normal cardiac auscultation is reassuring, though does not exclude the possibility that a cardiac structural abnormality is present. Auscultatory abnormalities, if properly appreciated and characterized, provide a starting point for confirmatory testing and management of cardiovascular disease.
New York City’s life expectancy is skyrocketing “If you want to live longer and healthier than the average American, come to New York City,” pronounced Mayor Michael Bloomberg as he released recent data on the city’s life expectancy. Since 1990, when life expectancy in the city trailed the U.S. average by three years, it has lengthened by eight years! How did this come about? To counter the alarming statistics, the city health department introduced a series of initiatives to alter the choices available to its residents. It mandated calorie labels for food sold in chain restaurants and banned trans fats. It prohibited smoking in public places and markedly increased taxes on cigarettes. Finally, it rolled out hundreds of miles of new bicycle lanes and papered subways with information campaigns about the risks of obesity and the benefits of healthier lifestyle choices including regular exercise.
(Source: Lancet, June 2012)
Noncaloric sweeteners might promote weight loss A recently published statement from the American Heart Association and the American Diabetes Association indicates that there is some data to suggest that noncaloric sweeteners may be used to replace sources of added sugars and that this substitution may result in modest calorie reductions and weight loss. (Source: Circulation, July 2012)
P S YC H O S O C I A L I S S U E S
Can pets influence our response to stress? Angela Fern, M.S. Senior Exercise Physiologist, Preventive Cardiology and Rehabilitation Beaumont Hospital, Royal Oak
Pets are increasingly used for advertising products on television and in magazines. We see animals in movies and Internet clips. Many businesses now allow their employees to bring their pets to work on selected days each year. Since 78.2 million dogs and 86.4 million cats ‘have homes’ in the United States, it is apparent that Americans are smitten with their pets. I’ve often wondered, “Do our pets help us deal with stress?” Although the term “stress” is understood by young and old alike, the meaning is relative. Stressors, which are triggers for stress, are not the same for every person. Our individual reaction to a stressor can make all the difference in our body’s response to it. All people, regardless of circumstance, experience stress, either eustress (good stress) or distress (bad stress) including the hassles of day-to-day living. It is one of the risk factors for coronary artery disease that is considered “modifiable,” which means that a positive change in our behavior can influence it. Unfortunately, chronic stress can have serious consequences. For example, takotsubo cardiomyopathy (“broken heart syndrome”) is a condition that causes heart attack-like signs and symptoms that is believed to be precipitated by stressful life events. There are three stages of stress, which are collectively known as the General
Adaptation Syndrome. Stage I is the alarm phase involving the “fight or flight” response, where hormones such as adrenaline and cortisol are released. In this stage, increases in heart rate, blood pressure, and breathing occur. Traffic congestion, hassles at work, or family arguments are examples of typical stressors. The second stage is known as resistance, in which we may experience stressful responses over time. The last stage is termed exhaustion because long term stress responses are believed to negatively affect our health, such as increasing risks for chronic disease, digestive problems, weight gain, depression and sleep disorders. Stress management is an important coping tool for everyone. As individuals, we respond to stress and subsequently, stress relief, differently. While people may disagree on which method is the best to deal with stress, it is vital that common stressors are recognized and handled. At the positive end of the spectrum is eustress, for example, planning a wedding or hosting family for the holidays, which usually ends well. However, the timeline to the finale can be wrought with many stressors. Distress can come in the form of a job loss, the death of a loved one, or as post traumatic stress disorder. The stress response can be severe and lasting and may contribute to chronic illness.
Pets, in addition to other factors, can play a role in reducing stress. There are many interventions to achieve stress management, which include “psychosocial support, regular exercise, stress reduction training, sense of humor, optimism, altruism, faith, and pet ownership” (Current Atherosclerosis Reports, Mar. 2006). Additionally, the web site, WebMD, lists several suggestions for ways to relax the body and mind, which include regular physical activity, breathing exercises, gardening, writing and playing with or caring for pets. In one study that examined cardiovascular reactivity, when pets (dogs or cats) were present, their owners had lower heart rates and blood pressure at rest, during mental arithmetic (where they also made the least amount of mistakes) and during hand submersion in ice water than when their spouses or friends were present. It was concluded that “pets can buffer reactivity to acute stress as well as diminish perceptions of stress” (Psychosomatic Medicine, Sep.- Oct. 2002). In another study that also tested mental stress in subjects performing mental arithmetic, all participants were taking the blood pressure drug, lisinopril. Subjects that also owned pets (dogs or cats) had significantly lower heart rate and blood pressure responses to mental stress than those taking the drug alone (Hypertension, Oct. 2001). In conclusion, research suggests that pets can help us feel better and relax. So the next time you feel stressed, spend some quality time with your favorite pet to reduce the associated demands on your heart. 5
C A R D I O VA S C U L A R S U R G E RY
Atrial fibrillation: Treatment options Phillip Robinson, M.D. Cardiovascular Surgeon Beaumont Hospital, Troy
Atrial fibrillation (a-fib) is a heart rhythm irregularity affecting approximately 3 million people in the United States. It is usually recognized by patients who notice that their heartbeats are erractic at times or that they are skipping beats. The older you are, the greater the risk for developing this abnormal heart rhythm. About 3 percent of patients in their Normal forties and up to 10 percent of those Left atrium in their eighties experience this irregular heart rhythm. Right atrium There are three classifications or Sinoatrial node types of a-fib. These are based on (pacemaker) the duration of time you spend in Atrioventricular a-fib, and what makes your heart node revert back into its normal rhythm, known as sinus rhythm. Many patients spend short periods of time in this rhythm and will spontaneously convert back to normal on their own. Others spend longer periods of time and may require electric shocking of the heart to return to a regular rhythm. For some patients, the heart may never resume its regular rhythm and the patient stays in a-fib permanently. The basic problem with this electrical conduction disturbance is that the upper chambers of the heart (the atria) do not beat in the usual fashion. The atria lose their ability to produce forceful contractions which adequately fill the lower pumping chambers (the ventricles). The consequences of this rhythm can include feelings of tiredness; fast, irregular hearts beats called palpations; or even strokes. In fact, the risk of a stroke is seven times higher for a patient in a-fib than a patient in normal sinus rhythm. Twenty five percent of all strokes in this country are from a-fib. These strokes are usually more debilitating than strokes from other reasons and often occur multiple times over a patientsâ€™ lifetime if not treated. The primary medical treatment for patients with a-fib uses medications to control the heart rate and lower the risk of strokes. Blood thinners such as Coumadin or newer medications reduce stroke risks, but can be associated with bleeding complications. Recently, newer medications have been introduced to help with some of the inconveniences associated with Coumadin like 6
frequent blood testing. Those patients that are very symptomatic and have trouble coping with normal daily activities while in this heart rhythm may require more aggressive treatment plans. This may involve using medications which can convert a-fib to sinus rhythm. However, the side effects of these medications are significant and can lead to even more serious complications. Highly symptomatic patients may require a procedure called ablation, which can also be used to treat a-fib. An ablation makes a precisely controlled scar on the inside or outside of the heart which isolates the diseased area of the heart where the a-fib starts from the healthy part of the heart which Atrial Fibrillation controls the normal rhythm. The scar is usually made by heating the heart tissue to a high temperature with lasers or other energy sources which produce the desired results. The scars are strategically placed around veins in the heart, which connect from the lungs, or other areas which are known to trigger the a-fib. These ablation lines can either be placed by specially trained cardiologists who perform the procedures through the groin like a heart catheterization, or for more difficult types of a-fib, by surgeons through very small incisions or robotically. The results have been very encouraging with a success rate ranging from 75 to 95 percent, depending on the type of a-fib. Successfully treated a-fib allows patients to be weaned from their medications and stop the blood thinners. For the best long-term chance to remain free from a-fib, patients should be very diligent in watching their blood pressure, keeping it as close to normal as possible. For patients with obstructive sleep apnea, a mask that keeps the airway open during sleep may solve the problem. A healthy lifestyle of exercise and weight control is also strongly encouraged.
Atrial Fibrillation Clinic At the Ernst Cardiovascular Center at Beaumont Hospital, Royal Oak campus there is an Atrial Fibrillation Clinic designed to offer patients the varied options available to treat this potentially debilitating arrhythmia. For more information on the Ernst Center, call 888-683-7678.
Simon R. Dixon, M.D., MBChB
FROM THE CHIEF
Chair, Department of Cardiovascular Medicine, Beaumont Hospital, Royal Oak
Common antibiotic increases risk of cardiovascular death Azithromycin (Zithromax or Z-Pak) is a popular antibiotic that is commonly used to treat upper respiratory tract infections. One of the important advantages of this antibiotic is that it can be taken for fewer days than other antibiotic medications. However, a recent study (New England Journal of Medicine, May 2012) raises concern that azithromycin is toxic to the heart and increases the risk of death during treatment.
increase risk of serious heart rhythm disturbances (such as threatening ventricular arrhythmias) due to their effect on prolonging vulnerable intervals on the electrocardiogram. Until now, azithromycin was thought to be free of any cardiotoxic effects.
Perspective It is important to understand that all antibiotics may cause serious side effects, so physicians must carefully weigh the pros Researchers at Vanderbilt University analyzed the medical and cons of treatment. The absolute risk of death associated records of 540,000 Tennessee Medicaid patients from 1996 with azithromycin in this study is actually quite small and to 2006 to compare the safety of azithromycin with other a single study alone should not be viewed as the definitive antibiotics including amoxicillin, ciprofloxacin and answer. For example, it is unclear whether the extra deaths in levofloxacin. The study demonstrated a this study were directly due to azithromycin 2.5 fold higher rate of death among patients or other factors associated with the patients’ Physicians should taking a five-day course of azithromycin medical condition. think twice about compared with amoxicillin, with an extra prescribing this Nevertheless, physicians should think twice 47 deaths for every 1 million prescriptions common antibiotic if about prescribing this common antibiotic of azithromycin. The risk of death was other comparable if other comparable agents are available, magnified in those patients with known heart agents are available, especially in patients with known heart disease. The risk of dying associated with especially in disease. It is also important to recognize that azithromycin was present only during the patients with known many prescriptions for antibiotics are course of antibiotic treatment and did not heart disease. inappropriate, so patients should ask their persist after the medication was completed. physician whether an antibiotic is absolutely Azithromycin is one of several agents in the necessary. For any patients currently taking macrolide class of antibiotics. Older azithromycin, we suggest consultation with macrolide antibiotics such as erythromycin your doctor to determine whether the and clarithromycin are well known to medication is right for you.
Lifestyle choices and the built environment Barriers to healthier lifestyle choices often include the built environment. For example, racial/ethnic minority and low-income communities have more convenient access to high-fat, high caloric fast food. In addition, these population subsets are often disadvantaged in access to recreation facilities, positive outdoor surroundings and protection from traffic. (Source: American Journal of Preventive Medicine, Oct. 2004; Circulation, Feb. 2012)
Health quote of the year Recently, Dr. Joseph Alpert, editor of the American Journal of Medicine, said, “You only have to exercise on the days that you eat.” (Source: American Journal of Medicine, Jan. 2011)
Time for a six-minute walk? Recently, researchers reported that cardiac patients who covered the shortest distance (bottom 25 percent) during a six-minute walk test, had four times the rate of new cardiovascular events over an eight-year follow-up period as compared with those who covered the most distance (top 25 percent). The ability of the walk test to predict cardiovascular events was similar to that of maximal treadmill exercise testing, highlighting the mantra ‘survival of the fittest.’ (Source: Archives of Internal Medicine, June 2010)
HELPFUL MEDICAL ADVICE
Flu facts for the cardiac patient Stephen Gunther, M.D. Staff Cardiologist Beaumont Hospital, Royal Oak
As we are out in the garden or on the golf course this summer, flu season is far from most of our minds. But it’s not too early to prepare. Influenza is a major cause of death and hospitalization, and creates an enormous public health cost. Patients with cardiovascular disease are at especially high risk. The stresses of pulmonary infection, fever and dehydration are poorly tolerated by those with impaired cardiovascular function and can cause a much higher complication rate. In addition, the influenza virus directly destabilizes atherosclerotic plaque – increasing the risk of plaque rupture and
blood vessel thrombosis. By triggering these causes of heart attack and stroke, influenza is potentially responsible for thousands of preventable deaths each year.
Despite its overwhelming benefit, less than 50 percent of persons at risk receive the flu vaccine every year.
Cardiovascular events and mortality peak in the winter months, with the seasonal increase following one to two weeks after the spread of flu in the community.
Early vaccination is critical and cardiac patients should know that the flu vaccine not only minimizes the inconvenience of flu symptoms and need for hospitalization, but saves lives. According to some reports, the rate of heart attack, stroke and out-of-hospital sudden cardiac death are markedly reduced in vaccinated individuals. Despite its overwhelming benefit, less than 50 percent of persons at risk receive the flu vaccine every year. The Centers for Disease Control and Prevention recommends vaccination for everyone over the age of 50, and for anyone with cardiovascular disease, regardless of age. The current flu vaccines are safe and inexpensive and can help ensure you are able to enjoy next summer’s pleasures.
CLINIC AL C ARDIOLOGY
The problem with abruptly stopping beta-blocker therapy Harold Friedman, M.D. Medical Director, Preventive Cardiology and Rehabilitation Beaumont Hospital, Royal Oak
Beta-blockers are a class of drug used to treat a variety of cardiovascular conditions. Referred to by either their generic names, which commonly end in “ol” (atenolol, metoprolol, nadolol, propranolol, timolol), or their brand names (Tenormin, Lopressor or Toprol, Corgard, Inderal and Blockadren), they work by affecting the response to certain nerve impulses throughout the body. These drugs are commonly used to treat hypertension, irregular heartbeats, rapid heart rates, anginal chest pain, heart attacks and congestive heart failure. Because beta-blockers are widely prescribed, understanding their safe use is important. Beta-blockers block adrenalin in the bloodstream from binding to beta-receptors on a variety of cells in the body. The receptors are part of the “flight or fight” stimulating mechanism. Beta-receptors are located in many cellular 8
sites, including the heart and blood vessels. With prolonged exposure to beta-blocker drugs, the body begins to adapt by increasing the numbers of receptors on each cell. This serves as a counter response to heighten adrenalin sensitivity. This adaptive response, which occurs in everyone, results in a series of predictable and serious problems if the medication is abruptly stopped. Abrupt drug discontinuation results in an upsurge in cellular adrenalin-like activity since more receptors have formed and many of these become unblocked. The response may include increased angina, accelerated heart rates, heart attack, stroke, and potentially dangerous spikes in blood pressure. Less serious symptoms include palpitations, increased perspiration and malaise. Such symptoms often occur in up to 50 percent of the patients with angina. Beta-blockers are typically tapered over 10 to 14 days in elective situations. If “rebound” symptoms appear, the dose or frequency of the beta-blocker can be modified. (continued on page 12)
G E R I AT R I C S
Exercise: The antidote to aging? Cindy Haskin-Popp, M.S. Exercise Physiologist, Preventive Cardiology and Rehabilitation Optimal Aging Program Beaumont Hospital, Royal Oak
Why do some individuals appear to age gracefully, while others are more likely to show and feel their years? Genetics of course play a role, but hereditary factors only make up part of the equation. According to the American College of Sports Medicine, aging is a complex process that is dependent upon primary aging factors, which occur naturally in the absence of known disease, and secondary aging influences, including lifestyle habits and the presence of chronic diseases (Medicine & Science in Sports & Exercise, July 2009). The body’s physiological systems are inevitably affected by changes related to normal aging, but the extent to which deterioration occurs is, in part, related to the older adult’s physical activity level. Common ailments that have been traditionally associated with aging, such as an increased prevalence of chronic diseases, decreased stamina, reduced muscular strength and endurance, loss of balance, increased risk for falls and bone fractures, cognitive dysfunction and loss of independent living are partially attributed to physical inactivity and disuse. Regular exercise can prevent, manage and largely reverse these effects, thereby improving the older adult’s mental and physical function while maintaining his or her independence. According to the President’s Council on Fitness, Sports & Nutrition, the most important components of fitness associated with healthy aging in older adults include muscular strength and endurance, aerobic endurance, flexibility and balance (Research Digest, June 2010). Strength training is particularly beneficial for older adults because of its role in increasing muscle mass, strengthening muscles and bones, improving balance, decreasing the risk for falls and bone fractures, mitigating the discomfort associated with arthritis and favorably modifying body weight and fat stores. Research has shown that resistance-based exercises can reverse the aging process by changing the gene expression of the mitochondria, the “powerhouses” of the muscle cells, to resemble the genetic profiles of younger people (PLoS ONE, May 2007). Fortunately, strength training benefits for the older adult can be achieved by a modest time commitment. Participating in resistance-based exercises that work the major muscle groups of the body (one set of 8 to 12 repetitions per exercise) on at least two days a week can enhance functional independence in older adults (Physical Activity Guidelines for Americans, 2008).
The incidence of chronic disease, such as cardiovascular disease, diabetes, arthritis and osteoporosis increases with age, with approximately 80 percent of older adults living with one or more of these conditions (The State of Aging and Health in America, 2007). Chronic illnesses can decrease quality of life by limiting the older adult’s ability to carry out activities of daily living. Aerobic exercise, such as brisk walking or riding a bike, plays an instrumental role in preventing and controlling these conditions and their consequences (Current Sports Medicine Reports, June 2004). Older adults who participate in regular aerobic training can expect to reclaim and maintain some of their youth through positive effects on the cardiovascular, pulmonary and musculoskeletal systems. These include: • Increased stamina/endurance: The oxygen requirement (amount of energy needed) for any given activity, such as vacuuming, is comparable among individuals, regardless of fitness level. Regular aerobic exercise increases the body’s ability to transport and utilize oxygen per heartbeat. Therefore, fit older adults have a greater energy reserve, which allows them to perform more work with less fatigue. • Improved blood sugar control: Cardiovascular training increases the body’s sensitivity to insulin. Consequently, the older adult’s muscles and body tissues are better able to extract and use sugar in the bloodstream, leading to normal circulating levels. Regular aerobic exercise also improves insulin’s response to blood sugar. • Weight management/improved body composition: The average inactive American adult will gain approximately 18 to 20 pounds between the ages of 18 to 55 years, with additional increases averaging 2 pounds per year over the next 10 years. This weight gain is primarily fat. Routine aerobic exercise helps to reduce body fat stores, particularly from the intra-abdominal area (Medicine & Science in Sports & Exercise, July 2009). • Blood pressure control: The Centers for Disease Control and Prevention report that approximately 64 percent of men and 70 percent of women ages 65 to 74 years have high blood pressure. Hypertension is a risk factor for stroke, kidney disease and heart disease. Participation in regular aerobic exercise decreases the risk of developing hypertension and modestly reduces blood pressure values in individuals with hypertension.
(continued on page 12) 9
VA S C U L A R S U R G E RY
Aneurysms: A bubble in the vascular system? O. William Brown, M.D. Director, Vascular Surgery Beaumont Hospital, Royal Oak
An aneurysm is a ballooning of an artery. It can occur anywhere in the body and most commonly involves the main artery called the aorta. The aorta carries blood from the heart and travels down the middle of the body. When it gets to the belly button, the aorta splits with one branch going Aorta exiting heart to each leg. Like balloons, when an aneurysm gets too big it can pop or Artery to rupture. If the aorta kidney ruptures, it can be fatal. Therefore, it is important to detect and treat aneurysms before they rupture. The chances of a successful recovery following an elective operation to repair an aortic aneurysm are approximately 98 percent. However, if an aneurysm is not treated until it ruptures, the chance of survival is 50 percent at best. The best ways to diagnose an aortic aneurysm are with an ultrasound of the abdomen, a physical examination, or both. People who suddenly feel a large pulse in their abdomen should make an appointment to see their physician. People over the age of 65, or people who have a
family history of aortic aneurysm, should undergo an ultrasound of the abdomen. Symptoms associated with aortic aneurysms depend upon the location of the aneurysm. People who have aneurysms of the thoracic aorta (portion of the aorta in the chest) may develop chest pain, upper back pain or shortness of breath. People with aneurysms of the abdominal aorta may develop severe lower back pain or abdominal pain. Aneurysms of the aorta that are larger than 5 centimeters (2 inches) usually require treatment. In the past, treatment required a large incision in the chest or abdomen and the replacement of the Heart aneurismal segment with an artificial artery. Today, we can treat most aneurysms Abdominal Abdominal aorta aortic with stent grafts. aneurysm These grafts are placed in the aorta through small incisions in each groin. Most people can go home the next day and resume full activity within one week. At Beaumont, we have the ability to treat not only routine aortic aneurysms, but also complex aneurysms of the aorta. Beaumont is one of approximately 25 centers in the country that has the capability of treating almost any type of aortic aneurysm with a stent graft, thus avoiding the need for a large incision and a lengthy hospital stay.
For further information regarding aortic aneurysms, please contact the Ernst Cardiovascular Center at Beaumont Hospital, Royal Oak at 888-683-7678. 10
Vigorous physical activity and weight loss According to a recent report, a 45-minute vigorous exercise bout resulted in a significant elevation in postexercise energy expenditure that persisted for 14 hours. The authors concluded that the nearly 200 calories expended after exercise above resting levels may have implications for weight loss and management. Moreover, the findings suggest that the calories expended from vigorous exercise are generally underestimated. (Source: Medicine & Science in Sports & Exercise, Sept. 2011)
Fitness trumps body weight in reducing mortality According to a new study, if you maintain or improve your fitness level, even if your body weight remains unchanged or increases, you can reduce your risk of death. In contrast, researchers found no association between changes in body fat or weight and death risk. (Source: Circulation, Dec. 2011)
COMMON Q & A
Robert N. Levin, M.D. Medical Director Coronary Care Unit Beaumont Hospital, Royal Oak
My nephew had aortic valve regurgitation and had to have his aortic valve replaced. I too, have aortic regurgitation, but my cardiologist is not replacing my valve. He is following me by performing echocardiograms every year. Why is he not fixing my valve? Aortic regurgitation is a condition characterized by backward leakage of blood into the left ventricle of the heart during the relaxation (diastolic) phase of the cardiac cycle, usually due to a defective aortic valve. Several conditions can cause this, including calcification and stiffening of the valve (often coincides with the aging process), rheumatic inflammation of the valve, valve infection or a congenitally abnormal valve. Over time, the left ventricle, or main pumping chamber of the heart, compensates for this extra (leaking) blood volume in two ways: it enlarges to accommodate the extra (regurgitant) blood volume or it starts to show signs of decreased pumping ability (ejection fraction).
Replacing or repairing regurgitant valves (as opposed to stenotic or narrowed valves) constitutes an “art” in that there is often a fairly long latent period until the patient becomes symptomatic and the valve needs to be replaced. Your cardiologist will likely advise that your valve be repaired or replaced when you start to show signs (on cardiac ultrasound) of enlargement of the left ventricle, a decrease in the heart’s ejection fraction or with associated symptoms (usually shortness of breath). In recent years, cardiologists have embraced a somewhat lower threshold to fix leaking heart valves, in that the morbidity and mortality of the procedure is far lower than it was in the past. Oftentimes, leaky valves can be repaired rather than replaced, which might be a more desirable solution. Another approach in patients who may be poor surgical candidates might be to replace the valve with a new valve mounted on a catheter, without performing open heart surgery.
I have been taking metoprolol for the past two years, which was prescribed by my cardiologist for episodes of paroxysmal supraventricular tachycardia (sudden rapid heart rate), along with mild elevation of my blood pressure. If I work out on my elliptical machine within a few hours of taking my metoprolol, I can only get my heart rate to 116 beats per minute (bpm). If 24 hours have passed since taking my pill, I can get my heart rate up to 140 bpm. Is my exercise doing any good for me if I can’t adequately increase my heart rate? Metoprolol is a beta-blocker and works by slowing the A: heart, especially during exercise. As long as the metoprolol is in your system, you may not be able to achieve your prescribed
target heart rate; however, you are still benefiting from the exercise. If you use the same workload, you are still doing the same amount of work but at a lower heart rate. A common misconception is that the rise in heart rate during exercise is what causes the body to become aerobically fit. But the increased heart rate during exercise is simply a marker for the real training stimulus – increased oxygen consumption and energy expenditure. Regardless of the heart rate response, exercise should generally feel fairly light to somewhat hard, and never hard. Don’t let beta blocker therapy “trump you” into thinking that you’re not getting enough exercise!
Diabetes epidemic? According to the Centers for Disease Control and Prevention, one in three U.S. adults could have diabetes in 2050. Why? The predicted increase is due to aging of the population, obesity, our habitually sedentary lifestyle (e.g., too little exercise, excessive sitting time), and increases in the population of minority groups that are at higher risk for developing type 2 diabetes. (Source: www.cdc.gov)
Unhealthy eating (continued from page 3)
Dietary and lifestyle priorities associated with cardioprotective benefits Consume more:
• fish and shellfish • whole grains • fruits • vegetables • nuts • low-fat or non-fat dairy products • vegetable oils* • water
• potatoes, refined grains, sugars • processed meats • sweetened beverages, diet sodas • grain-based desserts and bakery foods • fats, oils or foods containing partially hydrogenated vegetable oils • salt • alcohol+
* Examples include flaxseed, canola, and soybean oil
+ For adults who drink alcohol, no more than moderate consumption (i.e., up to 2 drinks/day for men, 1 drink/day for women) should be encouraged, ideally with meals.
Also: Stop cigarette smoking and avoid secondhand smoke, reduce food portion sizes, limit prolonged sitting (i.e., extended TV watching or computer interactions), increase daily physical activity and get enough sleep.
Exercise: The antidote to aging? (continued from page 9) • Improved cholesterol profile: The risk of developing elevated blood cholesterol levels increases with age. Routine aerobic training reduces this likelihood. Other studies have also shown (Preventive Cardiology, Fall 2005) that aerobic exercise can increase HDL cholesterol (the “good” cholesterol) by six percent. The results also indicated that cardiovascular training lowers the total cholesterol to HDL cholesterol ratio. Some exercise studies have reported that modest decreases in total cholesterol and Older individuals who LDL cholesterol (the “bad” cholesterol) can occur, have not exercised in especially with concomitant weight loss. years or who are physically limited by It is recommended that the older adult engage in chronic conditions can moderate-intensity aerobic exercise (e.g., walking at a still get health 2.5 to 4 mile per hour pace) for at least 150 minutes per benefits by exercising week (Physical Activity Guidelines for Americans, 2008). in 10 minute bouts This would equate to exercising approximately accumulated 30 minutes per day on at least 5 days of the week. throughout the day. In addition to aerobic and resistance exercise, flexibility and balance exercises help to minimize the effects of aging and increase the likelihood that older adults can extend their years of independent living. Poor flexibility can impair mobility and negatively affect the older adult’s ability to perform day-to-day tasks. Some studies suggest that range of motion exercises and stretching can increase the flexibility of the major joints (Medicine & Science in Sports & Exercise, July 2009). Flexibility exercises should be performed for varied muscle groups and each stretch should be held for 10 to 30 seconds and repeated four times (Current Sports Medicine Reports, June 2004). Balance training and fall-prevention activities, such as tai chi, should also be included in the older individual’s exercise regimen. Falls are the leading cause of death from injury in older adults (The State of Aging and Health in America, 2007). These accidents often lead to bone fracture, with a hip fracture being the most debilitating and lifethreatening complication. Approximately 20 percent of hip fracture sufferers die within the year as a result of their injury. Thus, older adults should perform balance training exercises three to four days per week. Older adults are highly encouraged to engage in structured aerobic exercise and increased lifestyle physical activity. Habitual physical activity can offset the negative impact of sedentary living on the aging process. Benefits can be obtained even if you haven’t exercised in years. The bottom line? Regular physical activity is a ‘time machine’ – an antidote to the aging process. Use it, or lose it.
STATE OF THE HEAR T LINE-UP Editor-in-chief: Barry Franklin, Ph.D. Co-editor: Simon Dixon, M.D. Associate editor: Robert Levin, M.D. Managing editor: Brenda White PANEL OF EXPER TS Clinical Cardiology: Aaron Berman, M.D.; Terry Bowers, M.D.; William Devlin, M.D.; Harold Friedman, M.D.; Andrew Hauser, M.D.; Robert Levin, M.D.; Steven Timmis, M.D.; Douglas Westveer, M.D.; David Forst, M.D. Interventional Cardiology: Steven Almany, M.D.; Nishit Choksi, M.D.; Phillip Kraft, M.D.; George Hanzel, M.D.; Dinesh Shah, M.D. Nursing: Steve Albertus, R.N.; Kathy Faitel, R.N. Pharmacology: Heidi Pillen, PharmD. Exercise Physiology/Fitness: Angela Fern, M.S.; Kirk Hendrickson, M.S.; Amy Fowler, B.S. Geriatrics: Michael Maddens, M.D.; John Voytas, M.D. Psychosocial Issues: Dan Stettner, Ph.D.; Gene Ebner, Ph.D. Electrophysiology: David Haines, M.D. Diagnostic Testing/Nuclear Medicine: Darlene Fink, M.D.; Ralph Gentry, R.T. (R) (MR) (CT); Gilbert Raff, M.D. Cardiovascular Surgery: Marc Sakwa, M.D.; Frank Shannon, M.D. Obesity, Diabetes, Metabolism: Wendy Miller, M.D.; Kerstyn Zalesin, M.D. Enhanced External Counterpulsation Therapy: Anne Davis, R.N.
Stopping beta-blocker therapy (continued from page 8)
Women’s Issues: Pamela Marcovitz, M.D.; Melissa Stevens, M.D.
If you suspect medication-related side effects, consult your physician immediately. There may be a different beta-blocker formulation that is better for you or a non-beta-blocker medication alternative.
To receive the State of the Heart e-newsletter, opt in at http://heart.beaumont.edu/ or scan our code below.
Beta-blocker therapy can be useful for preventing recurrent heart attacks and potentially fatal rhythm disturbances in heart attack survivors. Patients who may also benefit from these medications include the elderly and individuals with heart failure. Nevertheless, abruptly stopping beta-blocker treatment can lead to a rebound effect, including adverse signs and symptoms. In some cases, these may be life-threatening. As a reminder, I’d suggest making a copy of this label and pasting it on your medicine tray: 12